Hello, during my tests of AngelScript I've found a problem with strings as parameters (access violation). This problem occurs on Mingw (using gcc 3.3.1 and 3.4.2), but not on Visual .NET 2003. I've included a new test case in the test_feature project, file teststdstring.cpp (see appendix of this mail). Torsten // // This test shows how to register the std::string to be used in the scripts. // It also used to verify that objects are always constructed before destructed. // // Author: Andreas Jönsson // #include "utils.h" using namespace std; #define TESTNAME "TestStdString" static string printOutput; static void PrintString(string &str) { printOutput = str; } static void PrintStringVal(string str) { printOutput = str; } // This script tests that variables are created and destroyed in the correct order static const char *script = "void blah1()\n" "{\n" " if(true)\n" " return;\n" "\n" " string blah = \"Bleh1!\";\n" "}\n" "\n" "void blah2()\n" "{\n" " string blah = \"Bleh2!\";\n" "\n" " if(true)\n" " return;\n" "}\n"; static const char *script2 = "void testString() \n" "{ \n" " print(getString(\"I\" \"d\" \"a\")); \n" "} \n" "string getString(string ∈ str) \n" "{ \n" " return \"hello \" + str; \n" "} \n" "void testString2() \n" "{ \n" " string str = \"Hello World!\"; \n" " printVal(str); \n" "} \n"; static const char *script3 = "string str = 1; \n"; static void Construct1(void *o) { } static void Construct2(string &str, void *o) { } static void Destruct(void *o) { } static void StringByVal(string &str1, string str2) { assert( str1 == str2 ); } //--> new: object method string argument test class StringConsumer { public: void Consume(string str) { printOutput = str; } }; static StringConsumer consumerObject; //<-- new: object method string argument test bool TestStdString() { bool fail = false; asIScriptEngine *engine = asCreateScriptEngine(ANGELSCRIPT_VERSION); RegisterStdString(engine); engine->RegisterGlobalFunction("void print(string ∈)", asFUNCTION(PrintString), asCALL_CDECL); engine->RegisterGlobalFunction("void printVal(string)", asFUNCTION(PrintStringVal), asCALL_CDECL); engine->RegisterObjectType("obj", 4, asOBJ_PRIMITIVE); engine->RegisterObjectBehaviour("obj", asBEHAVE_CONSTRUCT, "void f()", asFUNCTION(Construct1), asCALL_CDECL_OBJLAST); engine->RegisterObjectBehaviour("obj", asBEHAVE_CONSTRUCT, "void f(string ∈)", asFUNCTION(Construct2), asCALL_CDECL_OBJLAST); engine->RegisterObjectBehaviour("obj", asBEHAVE_DESTRUCT, "void f()", asFUNCTION(Destruct), asCALL_CDECL_OBJLAST); engine->RegisterGlobalFunction("void StringByVal(string ∈, string)", asFUNCTION(StringByVal), asCALL_CDECL); //--> new: object method string argument test engine->RegisterObjectType("StringConsumer", 0, asOBJ_CLASS); engine->RegisterObjectMethod("StringConsumer", "void Consume(string str)", asMETHOD(StringConsumer,Consume), asCALL_THISCALL); engine->RegisterGlobalProperty("StringConsumer consumerObject", &consumerObject); //<-- new: object method string argument test COutStream out; engine->AddScriptSection(0, "string", script, strlen(script), 0); engine->Build(0, &out); int r = engine->ExecuteString(0, "blah1(); blah2();", &out); if( r < 0 ) { fail = true; printf("%s: ExecuteString() failed\n", TESTNAME); } engine->AddScriptSection(0, TESTNAME, script2, strlen(script2), 0); engine->Build(0, &out); engine->ExecuteString(0, "testString()", &out); if( printOutput != "hello Ida" ) { fail = true; printf("%s: Failed to print the correct string\n", TESTNAME); } engine->ExecuteString(0, "string s = \"test\\\\test\\\\\"", &out); // Verify that it is possible to use the string in constructor parameters engine->ExecuteString(0, "obj a; a = obj(\"test\")", &out); // Verify that it is possible to pass strings by value printOutput = ""; engine->ExecuteString(0, "testString2()", &out); if( printOutput != "Hello World!" ) { fail = true; printf("%s: Failed to print the correct string\n", TESTNAME); } printOutput = ""; engine->ExecuteString(0, "string a; a = 1; print(a);", &out); if( printOutput != "1" ) fail = true; printOutput = ""; engine->ExecuteString(0, "string a; a += 1; print(a);", &out); if( printOutput != "1" ) fail = true; printOutput = ""; engine->ExecuteString(0, "string a = \"a\" + 1; print(a);", &out); if( printOutput != "a1" ) fail = true; printOutput = ""; engine->ExecuteString(0, "string a = 1 + \"a\"; print(a);", &out); if( printOutput != "1a" ) fail = true; printOutput = ""; engine->ExecuteString(0, "string a = 1; print(a);", &out); if( printOutput != "1" ) fail = true; printOutput = ""; engine->ExecuteString(0, "print(\"a\" + 1.2)", &out); if( printOutput != "a1.2") fail = true; printOutput = ""; engine->ExecuteString(0, "print(1.2 + \"a\")", &out); if( printOutput != "1.2a") fail = true; engine->ExecuteString(0, "StringByVal(\"test\", \"test\")", &out); engine->AddScriptSection(0, TESTNAME, script3, strlen(script3), 0); if( engine->Build(0, &out) < 0 ) { fail = true; } //--> new: object method string argument test printOutput = ""; engine->ExecuteString(0, "consumerObject.Consume(\"This is my string\")", &out); if( printOutput != "This is my string") fail = true; //<-- new: object method string argument test engine->Release(); return fail; }

Thanks for letting me know. This is probably related to the difference in the calling conventions used by MinGW and MSVC++. I'll verify it and correct the problem for the next release.

In the meantime, you can probably bypass this by passing the string by reference instead of by value.

Regards,
Andreas

Passing the string by reference also does not work! No access violation, but an error message from the engine occurs.

Torsten

You need to implement the consumer as follows:

void Consume(string &str)
{
}

and register it as:

"void Consume(string ∈)"

<code>in</code>, <code>out</code>, and <code>inout</code> are keywords that tell the script compiler for what the reference is used.

I'm looking into this bug right now. I believe I'll have the fixed ready before long.

Fixed the bug. It will be in the next release.

Thanks for the excellent bug report.

Hi WitchLord,

the bug is solved, thank you for the fast correction!

Torsten